I am compelled by the notion of free will described by Schopenhauer (expanding on Kant). Namely, that 'one can do as he wills but not will as he wills'. Lived experience leads us to infer an indeterminate/inseparable energy/force/Will that we perceive with our senses and organize through the concepts of time/space/causality. However, we, being on the 'inside' of one particular object, are in a peculiar state: we are free to accept or reject this Will.
If I ask you to think of a number between 0 and 10, a number may pop up in your head (seemingly out of nowhere, though clearly through some process affected by genetics/neurochemistry). Despite this, you (whatever 'you' is) are still free to accept or reject this proposition.
In this sense, people can still be punished for accepting propositions of murder in some coherent way. You are affected by, but not the sum total of, your genetics and neurochemistry. Nevertheless, the latter might play a large role that we shouldn't discount.